<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
	</head>
	<body>
		<script type="text/javascript">
			//1.数值型
			console.log(100)//十进制
			console.log(0xff)//十六进制
			console.log(077)//八进制
			console.log(3.1415926)//
			console.log(3.5e3)//科学计数法
			
			console.log(typeof 100)//typeof 查看数值类型
			console.log(typeof 3.145)
			
			console.log(1/0) //infinity
			console.log(0/0) //NAN
			
			
			//2.字符串类型 string
			console.log("hello world")
			console.log('hello "manman" man')
			console.log("hello man 'wokanisee'")
			console.log(typeof "hello")
			
			
			/*转义字符
			\t  制表符
			\r  回车符
			\n  换行符
			\f  换页
			\'  '
			\"  "
			\\  \
			*/
		   
		   
			//布尔型
			console.log(true)
			console.log(false)
			var a=10;
			var b=20;
			console.log(a==b)
			console.log(typeof (a==b))
			
			//4.特殊类型
			//undefined 未定义
			var c;
			console.log(c)
			console.log(typeof c)
			
			//numll 空值
			var d = document.getElementById("div01")
			console.log(d)		//num
			console.log(d)		//object
				
			</object>
		</script>
	</body>
</html>
